Capacity and available bandwidth estimation may be important in many networking applications. Accurate estimation may allow for using available resources as efficiently as possible without hurting other co-existing flows or creating congestion. A way to regulate the usage of the resources may be to employ admission control. However, admission control may only be applied if a service provider owns the network. Thus, over-the-top (OTT) providers may not be able to offer services that benefit from admission control. Furthermore, admission control parameters may be preset which may lead to sub-optimal operation in networks where available resources are time-varying. Real-time estimations may be used to improve the efficiency of admission control by setting parameters more appropriately. In cases where admission control is not feasible, real-time measurements may be useful.